1. Field of the Invention
This invention relates to a gas-cooled generator, in particular a generator forming part of a turboset.
2. Brief Description of the Related Art
Generators are known which comprise a rotor and stator with a gap between them. The stator comprises a core and windings which form a winding overhang at each end of the stator. The rotor has axially extending cooling channels communicating with end portions of the rotor beyond ends of the stator core and has radially extending cooling channels communicating between the axially extending cooling channels and the said gap. The stator core has cooling ducts communicating between the said gap and a region for receiving gaseous coolant outside the stator core; the generator further comprises cooling apparatus communicating with the said receiving region.
In some known generators, the rotor, stator, and cooling apparatus are in an enclosure filled with the gaseous coolant, which is driven through the cooling apparatus by fans mounted on the ends of the rotor. From the cooling apparatus separate streams of gaseous coolant under pressure flow to the stator and to the rotor. In the stator the gaseous coolant flows radially inwards or outwards or alternately inwards and outwards.
Such generators suffer from losses due to the driving of the fans and friction of the gaseous coolant.